Complement and Osteoporosis

补体和骨质疏松症

• 批准号: 8544974
• 负责人: JAMES E DENNIS
• 金额: $ 35.86万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-15 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8544974
• 关键词: Accounting; Address; Affect; Biological Assay; Bone Marrow; Bone Marrow Cells; Bone Resorption; C57BL/6 Mouse; Cells; Ceramics; Complement; Complement 1q; Complement 3; Complement Activation; Complement Factor D; Complement Receptor; Complement component C1; Complex; Equilibrium; Estrogens; Goals; Hematopoietic; Hematopoietic stem cells; Homeostasis; Human; Immune; Immunology; Implant; In Vitro; Knockout Mice; Laboratories; Lead; Link; Mediating; Mesenchymal Stem Cells; Methods; Modeling; Mus; Osteoblasts; Osteoclasts; Osteogenesis; Osteoporosis; Ovariectomy; Pathway interactions; Postmenopausal Osteoporosis; Postmenopause; Production; Regulation; Role; Signal Transduction; Stem cells; Structure; Testing; Time; Tissues; Transplantation; Umbilical Cord Blood; Wild Type Mouse; X-Ray Computed Tomography; base; bone; bone loss; bone turnover; cell type; clinically relevant; complement deficiency; complement system; cytokine; deprivation; dosage; drug development; effective therapy; implantation; in vivo; inhibitor/antagonist; interest; novel; novel strategies; osteogenic; prevent; progenitor; receptor; research study; skeletal; transcription factor

DESCRIPTION (provided by applicant): Recent results in our laboratories have revealed a new and unexpected relationship between the complement system and post-menopausal bone loss, which has the potential to lead to new therapies for osteoporosis. These studies revealed that mice lacking the C3 component of the complement system were protected from bone loss after ovariectomy (OVX), as shown by micro-computed tomography (microCT) analysis. Our in vitro studies revealed that bone marrow cells from complement receptor-deficient mice had decreased capacity to differentiate into functional osteoclasts. Further, inhibition of complement signaling suppressed human osteoclast differentiation from hematopoietic progenitors. Based on these results, it is hypothesized that the complement system is a key regulator of bone balance and a potential target for the treatment of osteoporosis. To address this hypothesis, two Aims are proposed. Aim 1 will examine which complement activation pathway is involved, and how complement and complement receptor deficiency impact in vivo bone turnover by assessing bone structure in several OVXed complement knockout mice (Factor D-/-, C1q-/-, MBL-/-, C3-/-, C3aR-/- ,C5aR-/-, and C3aR-/-C5aR-/-) and wild type (WT) controls; microCT and bone histomorphometry will be the primary readouts. Aim 1 also will examine the role of local complement production in the regulation of bone balance using cross-implantation studies where mesenchymal stem cells (MSC) form ectopic bone in porous ceramic carriers. Aim 2 will test the use of complement receptor inhibitors as a means of preventing osteoporosis both in WT mice and humanized mice. WT (C57BL/6) mice, human umbilical cord blood stem cell-implanted NSG (NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ) mice, human MSC-implanted NSG mice, and both human umbilical cord blood stem cell and MSC-implanted NSG mice will be OVXed, treated, and assessed by microCT and bone histomorphometry. A novel aspect of the Aim 1 studies is the use of ectopically formed bone from MSCs isolated from the knockout mice that are then implanted into WT mice, and vice versa, which are then assayed for histomorphometric bone parameters - this allows for determination of the role of local complement deficiency of the MSCs on bone formation and loss, and also probes the effect of complement deficiency in hematopoietic cells when WT MSCs are implanted into the complement knockout mice. The complement receptor antagonists treatment experiments in Aim 2 using WT mice and different humanized mice are the most clinically relevant, and will address the potential of using these inhibitors for treating or preventing osteoporosis in humans. These studies will clarify how diminished complement signaling affects osteoblast and osteoclast differentiation in estrogen deprivation induced bone loss. The long-term goal of these studies is to develop new therapies to treat or prevent osteoporosis.

描述（由申请人提供）：我们实验室的最新结果揭示了补体系统与绝经后骨质流失之间存在新的意外关系，这有可能导致新的骨质疏松症治疗。这些研究表明，缺乏补体系统C3成分的小鼠受到卵巢切除术（OVX）后的骨质损失，如微型计算机（Microct）分析所示。我们的体外研究表明，来自补体受体缺陷小鼠的骨髓细胞已降低分化为功能性破骨细胞的能力。此外，抑制补体信号传导抑制了与造血祖细胞分化的人骨细胞分化。基于这些结果，假设补体系统是骨平衡的关键调节剂，也是治疗骨质疏松症的潜在靶标。为了解决这一假设，提出了两个目标。 AIM 1将检查涉及哪种补体激活途径，以及补体和补体受体缺乏如何通过评估几个OVX的骨结构中的骨结构（因子D-/ - ，C1Q - / - ，MBL - / - ，C3 - / - ，C3 - / - ，C3AR-，C5AR---，C5AR - / - ，C5AR） - / - - 和C3AR - 和C5AR - / - - - 和C5AR - / - - 和C5AR - 和C5AR - 和 - 和C5AR - 和C5AR - 和C5AR - 和C5AR-和C5AR - 和C5AR-和C5AR-和C5AR - 和C5AR-- MicroCT和骨骼组织形态计量学将是主要读数。 AIM 1还将通过跨植入研究研究中质感干细胞（MSC）在多孔陶瓷载体中形成异位骨的跨植入研究中，研究局部补体产生在调节骨平衡中的作用。 AIM 2将测试补体受体抑制剂作为预防WT小鼠和人源化小鼠中骨质疏松症的一种手段。 WT（C57BL/6）小鼠，人脐血血液干细胞扩散的NSG（NOD.CG-PRKDCSCID IL2RGTM1WJL/SZJ）小鼠，人类MSC埋入的NSG小鼠和MSC-imbilical ply and Mimbilical nsg and Mimbilical insed ns-implated and Mimbilical and insed and nsg and nsg and ther nsg and ther nsg and ov and ov and of of of of of ov of ov ov ov ov ov ov ov ov ov ov of组织形态法。目的1研究的一个新方面是使用从敲除小鼠中分离出的MSC的骨骼形成的骨骼，然后将其植入WT小鼠中，反之亦然，然后将其用于组织形态骨参数，这允许确定MSC在骨骼形成和造成的效果时，还可以确定局部互补仪的作用。植入补体敲除小鼠中。使用WT小鼠和不同的人源化小鼠在AIM 2中的补体受体拮抗剂治疗实验是临床上最相关的，并且将解决使用这些抑制剂治疗或预防人类骨质疏松症的潜力。这些研究将阐明补体信号的减少如何影响雌激素剥夺引起的骨质流失的成骨细胞和破骨细胞分化。这些研究的长期目标是开发新的疗法来治疗或预防骨质疏松症。